Pipeline dredger

ABSTRACT

A pipeline dredger, including a compressed air gun and a sealing apparatus, wherein the compressed air gun includes an L-shaped air pipe, a cavity body and a gun handle; an exhaust apparatus is arranged in the cavity body; a sealed compressed air chamber is formed between the exhaust apparatus and the cavity body; the exhaust apparatus includes a tubular connecting pipe and an exhaust pipe connected mutually; one end of the exhaust pipe is connected with the L-shaped air pipe, and the other end is a connecting end; one end of the connecting pipe is a chamber, and the other end is connected with a pressure release valve; the connecting end is inserted into the chamber; a vent hole is formed in an inner wall of the chamber so that the chamber is communicated with the compressed air chamber; a piston structure which is always abutted against the connecting end is arranged in the chamber; the piston structure separates the chamber from the exhaust pipe; a pressure release airflow generated during pressure release of the pressure release valve flows into the chamber from the compressed air chamber and drives the piston structure to separate from the connecting end so that the airflow flows into the exhaust pipe from the compressed air chamber through the chamber and is discharged from the L-shaped air pipe; the sealing apparatus comprises an air-filled bag installed on the L-shaped air pipe; and the inflated air-filled bag can block a pipeline opening.

TECHNICAL FIELD

The present invention belongs to the field of cleaning appliances, and particularly relates to a pipeline dredger.

BACKGROUND

In daily life, it is a common problem that a sewer is blocked by foreign matter. Therefore, a pipeline dredger is one of essential cleaning tools in families. The pipeline dredger is frequently used for dredging a blocking problem in household commodes, squatting pots, floor drains, vegetable basins, pools, washbasins, bathtubs, shower rooms, etc. Existing pipeline dredgers are generally divided into two types: mechanical pipeline dredgers and pneumatic pipeline dredgers. The mechanical pipeline dredgers achieve a purpose of dredging a pipeline by extending into the pipeline by means of flexibility and retractility of soft steel wires, rotating the soft steel wires and carrying over the foreign matter. However, in a use process, manual operation is needed, labor intensity is high and the soft steel wires are easy to scratch the pipeline. Moreover, the used steel wires have peculiar smell, and are unsanitary and inconvenient for storage. The pneumatic pipeline dredgers dredge the pipeline by means of an airflow with high intensity of pressure. Generally, a compressed air pump, a motor and a sealing apparatus for sealing a pipeline opening need to be configured, so the cost is relatively high. Operation is inconvenient because of complicated structure; and storage is difficult.

SUMMARY

The present invention provides a pipeline dredger suitable for dredging sewerages and realizing simple operation, sanitation and safety, no damage to pipelines and easy storage.

A technical solution adopted to solve the above technical problems in the present invention is as follows: A pipeline dredger comprises a compressed air gun and a sealing apparatus, wherein the compressed air gun comprises an L-shaped air pipe, a cavity body and a gun handle; an exhaust apparatus is arranged in the cavity body; a sealed compressed air chamber is formed between the exhaust apparatus and the cavity body; the exhaust apparatus comprises a tubular connecting pipe and an exhaust pipe connected mutually; one end of the exhaust pipe is connected with the L-shaped air pipe, and the other end is a connecting end; one end of the connecting pipe is a chamber, and the other end is connected with a pressure release valve arranged in the gun handle; the connecting end is inserted into the chamber and is connected and fixed; a vent hole is formed in an inner wall of the chamber so that the chamber is communicated with the compressed air chamber; a piston structure which is always abutted against the connecting end is arranged in the chamber; the piston structure separates the chamber from the exhaust pipe; a pressure release airflow generated during pressure release of the pressure release valve flows into the chamber from the compressed air chamber and drives the piston structure to separate from the connecting end so that the airflow flows into the exhaust pipe from the compressed air chamber through the chamber and is discharged from the L-shaped air pipe; the sealing apparatus comprises an air-filled bag sleeved on an outer side of the L-shaped air pipe; and the inflated air-filled bag can block a pipeline opening.

Preferably, the piston structure comprises a spring and a movable air plug for connecting the spring; the other end of the movable air plug is abutted against the end part of the connecting end; an external diameter of the movable air plug is gradually increased from a direction away from the connecting end to a direction close to the connecting end; and the external diameter of one end of the movable air plug abutted against the connecting end is greater than a maximum external diameter of the connecting end and less than an internal diameter of the chamber.

Preferably, an inserting depth of the connecting end in the chamber is greater than a distance between the vent hole and an end surface of an opening of the chamber.

Preferably, the cavity body comprises a cavity body shell and a connecting piece connected coaxially; a tubular air outlet pipe is also arranged on one end of the cavity body close to the exhaust pipe; and the exhaust pipe is connected with the air outlet pipe and is connected to the L-shaped pipe through the air outlet pipe.

Preferably, a button for controlling the pressure release valve and an inflating mouth externally connected with an inflating device are arranged on the gun handle; an inflating opening communicated to the compressed air chamber is arranged in the connecting piece; the pressure release valve is communicated with the connecting pipe; and the inflating opening is communicated with the inflating mouth.

Preferably, a pressure gauge is also arranged on the gun handle; a three-way pipe is arranged in the middle of a first hose; a second hose is arranged between the three-way pipe and the pressure gauge; and the pressure gauge displays intensity of pressure in the compressed air chamber and the chamber.

Preferably, an arc-shaped bulge is arranged at the opening of the end part of the air outlet pipe along a circumferential direction; the L-shaped pipe comprises a first air pipe and a second air pipe vertically connected; a spherical bayonet and a sealing knob sleeved on an outer ring of the spherical bayonet are arranged on the outer side of the end part of the first air pipe; a spherical chamber for inserting the arc-shaped bulge is arranged in the spherical bayonet; an internal diameter of the spherical chamber is equal to or less than a maximum external diameter of the arc-shaped bulge; a plurality of notches are arranged in the spherical bayonet along the circumferential direction of the opening; and the notches start from the opening and extend along the direction of the first air pipe.

Preferably, a safety plug and a safety plug hole penetrating through the connecting piece and communicated to the compressed air chamber are also disposed on the connecting piece; the safety plug is inserted into the safety plug hole; one end of the safety plug is sleeved with a safety spring; the safety spring generates an acting force facing the compressed air chamber to the safety plug; and the other end of the safety plug is sleeved with a plurality of safety washers and blocks the safety plug hole.

Preferably, the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.

Preferably, an air delivery pipe is arranged between the air-filled bag and the pressurization airbag; a deflation valve is arranged on the air delivery pipe; an air inlet hole for unidirectional air intake is formed in the pressurization airbag; and the deflation valve can be pressed to discharge inflated air in the air-filled bag.

Compared with the prior art, the pipeline dredger of the present invention forms an airflow with strong intensity of pressure within short time to dredge blocking stuff, and is convenient and rapid in use; the airflow may not damage pipelines; the sealing action of the sealing apparatus prevents the airflow from rushing out of a drain opening and carrying over dirty water and substances; and the pipeline dredger is sanitary and safe, compact in volume and easy for storage.

DESCRIPTION OF DRAWINGS

FIG. 1 is a structural schematic diagram of a pipeline dredger of the present invention.

FIG. 2 is an exploded schematic diagram of a compressed air gun of a pipeline dredger of the present invention.

FIG. 3 is an internal schematic diagram of a gun handle of a compressed air gun of a pipeline dredger of the present invention.

FIG. 4 is a schematic diagram of a sealing apparatus of a pipeline dredger of the present invention.

FIG. 5 is a sectional schematic diagram of a cavity body of a pipeline dredger of the present invention.

DETAILED DESCRIPTION

The present invention is further described below in detail in combination with the drawings and embodiments.

As shown in FIG. 1, FIG. 2 and FIG. 5, a pipeline dredger comprises a compressed air gun 1 and a sealing apparatus 2, wherein the compressed air gun 1 comprises an L-shaped pipe 21, a cavity body 12 and a gun handle 11; and the cavity body 12 comprises a cavity body shell 121 and a connecting piece 14 connected coaxially. A button 111, an inflating mouth 112 and a pressure gauge 113 are installed on the gun handle 11. The gun handle 11 comprises a grip 114. The button 111 is disposed above the grip 114, which is convenient for a user to enable a thumb to be just located above the button 111 when the user holds the grip 114 with a single hand so that the button 111 is pressed more conveniently and quickly. The inflating mouth 112 can be externally connected with an inflating device. Preferably, the inflating mouth 112 in the present embodiment is a common American air valve which can be inflated with an inflater in daily life. The pressure gauge 113 is installed on a side surface of the gun handle 11.

An exhaust apparatus is arranged in the cavity body 12. A sealed compressed air chamber 15 is formed between the exhaust apparatus and the cavity body 12. The exhaust apparatus comprises a tubular exhaust pipe 122 and a connecting pipe 128 which are connected. A tubular air outlet pipe 13 is also arranged on one end of the cavity body 12 close to the exhaust pipe 122. The air outlet pipe 13 is connected to the L-shaped pipe 21. One end of the exhaust pipe 122 is inserted into the air outlet pipe 13 and is connected to the L-shaped pipe 21 through the air outlet pipe 13. A first sealing washer 161 with a sealing action is disposed at a joint of the exhaust pipe 122 and the air outlet pipe 13. The other end of the exhaust pipe 122 is a connecting end 123. A chamber 129 is arranged at one end of the connecting pipe 128. The connecting end 123 is inserted into the chamber 129 of the connecting pipe 128, and is connected and fixed through a thread. A second sealing washer 162 is disposed at a joint of the connecting end 123 and the chamber 129, and performs a sealing action. The other end of the connecting pipe 128 extends out of the connecting piece 14 and is connected and fixed with the connecting piece 14 through the thread. A third sealing washer 129 with a sealing action is disposed at a joint of the connecting pipe 128 and the connecting piece 14. A vent hole 127 is fowled in a side wall of the chamber of the connecting pipe 128 so that the chamber 129 is communicated with the compressed air chamber 15. A spring 125 and a movable air plug 124 are also disposed in the chamber. One end of the spring 125 is abutted in the chamber, and the other end is abutted against the movable air plug 124. The movable air plug 124 is abutted against the end part of the connecting end of the exhaust pipe 122. A horizontal section of the movable air plug 124 is gradually increased from a direction towards the connecting end 123; and the external diameter of one end of the movable air plug 124 abutted against the connecting end is greater than a maximum external diameter of the connecting end and less than an internal diameter of the chamber so that the movable air plug 124 can block the connecting end. Since the spring 125 is always in a compressed state after the connecting end 123 is inserted into the chamber 129 and fixed, the movable air plug 124 is tightly close to the end part of the connecting end 123 under the action of rebound force of the spring 125 and blocks communication between the exhaust pipe 122 and the chamber 129. Since the inserting depth of the connecting end 123 in the chamber 129 is greater than the distance between the vent hole 127 and the end surface of the opening of the chamber, the movable air plug 124 is located between the vent hole 127 and the spring 125.

As shown in FIG. 2 and FIG. 3, the gun handle 11 and the connecting piece 14 are fixed through a bayonet. A pressure release valve 119 connected with the button 111 is arranged in the gun handle 11. The button 111 is used to control the pressure release valve 119 to release pressure. The pressure release valve 119 is connected with one end of the connecting pipe 128 extending from the connecting piece 14 through a first hose 115 arranged in the gun handle 11. A three-way valve 116 is arranged in the middle position of the first hose 115. The three-way valve 116 is connected with the pressure gauge 113 through a second hose 117 so that the pressure release valve 119 and the pressure gauge 113 are communicated with the compressed air chamber 15 through a chamber 129 in the connecting pipe 128. The pressure gauge 113 can intuitively display intensity of pressure of air in the compressed air chamber 15. A third hose 118 is also arranged in the gun handle 11. The third hose 118 is connected with the inflating mouth 112 and an inflating opening 141 which is arranged on the connecting piece. The inflating opening 141 is communicated to the compressed air chamber 15. When a user inflates through the inflating mouth 112, the air enters the cavity body 12 through the third hose 118 and the inflating opening 141. Because the movable air plug 124 blocks the connecting end of the exhaust pipe 122 in the chamber 129 of the connecting pipe 128, the air in the compressed air chamber 15 and the chamber 129 cannot be discharged from the compressed air gun 1 through the exhaust pipe 122 and the air outlet pipe 13. Finally, compressed air is formed in the compressed air chamber 15.

When the compressed air chamber 15 is inflated to reach an appropriate value of intensity of pressure, the value of intensity of pressure shall be matched with the elasticity of the spring 125. Preferably, the size of the intensity of pressure of the compressed air chamber 15 is selected as 0.3 to 0.5 MPa when the pipeline is dredged, so that air pressure in the compressed air chamber 15 and the chamber 129 is always kept in a certain state. The user presses the button 111 to control the pressure release valve 119 to release the air so as to form a pressure release airflow. The pressure release airflow flows into the chamber 129 in the connecting pipe 128 through the vent hole 127 from the compressed air chamber 15, flows towards the pressure release valve 119 through the first hose 115 and is finally discharged out. The pressure release airflow flows through the movable air plug 124. Because the external diameter of one end of the movable air plug 124 abutted against the connecting end 123 is less than the internal diameter of the chamber 129 and is greater than the maximum external diameter of the connecting end 123, the pressure release airflow passes through the movable air plug 124 in short time and generates a thrust which enables the movable air plug 124 to keep away from the connecting end. The thrust is greater than the elasticity of the spring in short time, causing that the movable air plug 124 is separated from the connecting end 123 of the exhaust pipe 122 so that the compressed air chamber 15, the chamber 129 in the connecting pipe 128, the air outlet pipe 13 of the exhaust pipe 122, and the exhaust passage formed by the L-shaped pipe 21 are communicated. The airflow of the compressed air flows into the exhaust pipe 122 after entering the chamber 129 through the vent hole 127 from the compressed air chamber 15, and is discharged out after flowing through the air outlet pipe 13 and the L-shaped pipe 21.

A safety plug 142 and a safety plug hole which penetrates through the connecting piece 14 and is communicated to the compressed air chamber 15 are also arranged on the connecting piece 14. The safety plug 142 is inserted into the safety plug hole. A safety spring 144 is sleeved on one end of the safety plug 142 and generates an acting force facing the compressed air chamber 15 to the safety plug 142. Because the other end of the safety plug 142 away from the safety spring 144 is sleeved with a plurality of safety washers 146, preferably two safety washers 146 are arranged in the present embodiment and the safety washers 146 block the safety plug hole under the drive of the safety plug 142 so that the safety plug hole cannot pass through the airflow. When the intensity of pressure of the compressed air inflated into the compressed air chamber 15 is greater than a safety value, the safety spring 144 is further compressed and the safety plug 142 moves towards a direction away from the compressed air chamber 15. At this moment, both ends of the safety plug hole are communicated and the compressed air is partially discharged out through the safety plug hole. After the intensity of pressure is decreased, the safety spring 144 pushes the safety washers 146 of the safety plug 142 to block the safety plug hole, and finally, the intensity of pressure in the compressed air chamber 15 is kept within a safety range.

As shown in FIG. 1 and FIG. 4, an arc-shaped bulge 131 for connecting the sealing apparatus 2 is arranged along the circumferential direction at the opening of the end part of the air outlet pipe 13. The sealing apparatus 2 comprises an L-shaped pipe 21, an air-filled bag 22 sleeved on the outer side of the L-shaped pipe 21, and a pressurization airbag 24 connected with the air-filled bag 22. The L-shaped pipe 21 comprises a first air pipe 211 and a second air pipe 212 which are mutually connected. The first air pipe 211 and the second air pipe 212 are mutually perpendicular and form an L-shaped ventilation pipeline in the present embodiment. A spherical bayonet 214 for connecting the arc-shaped bulge 131 and a sealing knob 213 sleeved on an outer ring of the spherical bayonet 214 are arranged on the end part of the outer side of the first air pipe 211. A spherical chamber is arranged in the spherical bayonet 214. An internal diameter of the spherical chamber is equal to or slightly less than a maximum external diameter of the arc-shaped bulge 131 so that a sealing effect is achieved after the arc-shaped bulge 131 is inserted into the spherical chamber. A plurality of notches 215 are arranged in the spherical bayonet 214 at intervals along the circumferential direction of the opening. The notches 215 extend to the end part of the spherical bayonet 214. The notches 215 enable the edge of the end part of the spherical bayonet 214 to have certain elasticity for the convenience of inserting the arc-shaped bulge 131. An external thread is also arranged on an external surface of the spherical bayonet 214. The external thread is matched with the internal thread arranged on the inner ring of the sealing knob 213. After the spherical bayonet 214 is inserted at the opening of the air outlet pipe 13, the sealing knob 213 is rotated and fixed to generate a pressing force on the spherical bayonet 214, so as to limit outward expansion of the edge of the opening of the spherical bayonet 214 along the radial direction, prevent the arc-shaped bulge 131 from separating from the spherical bayonet 214 and play a sealing and fastening effect. When the sealing knob 213 is rotated and loosened, the arc-shaped bulge 131 can be pulled out of the spherical bayonet 214 for the convenience of disassembly and assembly. Because the external surface of the arc-shaped bulge 131 and the surface of the spherical chamber of the spherical bayonet 214 are smooth circular arc surfaces and the arc-shaped bulge 131 and the spherical bayonet 214 can be deflected within an angular range of 30°, it is convenient for the user to adjust the L-shaped pipe 21 according to a use environment and adjust an air outlet direction of the compressed air gun 1.

A circle of air-filled bag 22 is fixed to the outer side of the second air pipe 212 along the circumferential direction. The external diameter of the air-filled bag 22 extends along an opposite direction of the opening of the second air pipe 212 and is gradually increased. Moreover, the air-filled bag 22 is made of elastically deformable material. In the present embodiment, the air-filled bag 22 is preferably made of rubber material. The external diameter of the expanded air-filled bag 22 has a slope along the extension direction of the second air pipe 212, thereby enhancing the sealing effect of blocking the pipeline opening by the air-filled bag 22. The air-filled bag 22 is connected with the pressurization airbag 24 through an air delivery pipe 23. A unidirectional vented deflation valve 25 is arranged at the joint of the pressurization airbag 24 and the air delivery pipe 23. An air inlet hole 241 for unidirectional air intake is formed in the pressurization airbag 24. When the user repeatedly presses the pressurization airbag 24, outside air enters the pressurization airbag 24 in a single direction from the air inlet hole 241, and flows into the air-filled bag 22 in a single direction through the deflation valve 25 so that the air-filled bag 22 is expanded to completely block the pipeline opening. When the user presses the deflation valve 25, the deflation valve 25 is communicated with the outside air. Because the intensity of pressure of the air in the expanded air-filled bag 22 is greater than the outside air, the air in the air-filled bag 22 flows through the air delivery pipe 23 and is discharged from the deflation valve 25. After the volume of the air-filled bag 22 is decreased, the sealing apparatus 2 can be conveniently withdrawn from the pipeline opening.

When the sealing apparatus 2 is connected with the air outlet pipe 13 of the compressed air gun 1, the user can place the sealing apparatus 2 at a drain opening of a commode and repeatedly extrude the pressurization airbag 24 to inflate the air-filled bag 22 for expanding the air-filled bag 22. Finally, the drain opening of the whole commode is full with the sealing apparatus 2, thereby forming a sealed space. Then, the user regulates a relative angle between the compressed air gun 1 and the sealing apparatus 2 to an appropriate position, inflates the compressed air gun 1 and finally presses the button 113 to discharge the compressed air from the air outlet pipe 13. The compressed air enters the L-shaped pipe 21 through the air outlet pipe 13 via a generated strong airflow, and enters the drain opening of the commode after passing through the L-shaped pipe 21. The sewerage of the commode forms a strong airflow in short time to dredge blocking stuff, which is convenient and quick in use. The airflow may not damage the pipeline, prevents the airflow from rushing out of the drain opening and carrying over dirty water and substances, and is sanitary and safe. Moreover, the pipeline dredger is compact in volume and easy for storage.

Finally, it should be noted that the above embodiments are only used for describing the technical solution of the present invention rather than limitation. Although the present invention is described in detail by referring to the above embodiments, those ordinary skilled in the art should understand that: the technical solution recorded in each of the above embodiments can be still amended, or some technical features therein can be replaced equivalently. However, these amendments or replacements do not enable the essence of the corresponding technical solution to depart from the spirit and the scope of the technical solution of various embodiments of the present invention. 

What is claimed is:
 1. A pipeline dredger, comprising a compressed air gun and a sealing apparatus, wherein the compressed air gun comprises an L-shaped air pipe, a cavity body and a gun handle; an exhaust apparatus is arranged in the cavity body; a sealed compressed air chamber is formed between the exhaust apparatus and the cavity body; the exhaust apparatus comprises a tubular connecting pipe and an exhaust pipe connected mutually; one end of the exhaust pipe is connected with the L-shaped air pipe, and the other end is a connecting end; one end of the connecting pipe is a chamber, and the other end is connected with a pressure release valve arranged in the gun handle; the connecting end is inserted into the chamber and is connected and fixed; a vent hole is formed in an inner wall of the chamber so that the chamber is communicated with the compressed air chamber; a piston structure which is always abutted against the connecting end is arranged in the chamber; the piston structure separates the chamber from the exhaust pipe; a pressure release airflow generated during pressure release of the pressure release valve flows into the chamber from the compressed air chamber and drives the piston structure to separate from the connecting end so that the airflow flows into the exhaust pipe from the compressed air chamber through the chamber and is discharged from the L-shaped air pipe; the sealing apparatus comprises an air-filled bag sleeved on an outer side of the L-shaped air pipe; and the air-filled bag can block a pipeline opening.
 2. The pipeline dredger according to claim 1, wherein the piston structure comprises a spring and a movable air plug for connecting the spring; the movable air plug is abutted against an end part of the connecting end; an external diameter of the movable air plug is gradually increased along a direction towards the connecting end; and an external diameter of one end of the movable air plug abutted against the connecting end is greater than a maximum external diameter of the connecting end and less than an internal diameter of the chamber.
 3. The pipeline dredger according to claim 2, wherein an inserting depth of the connecting end in the chamber is greater than a distance between the vent hole and an end surface of an opening of the chamber.
 4. The pipeline dredger according to claim 2, wherein the cavity body comprises a cavity body shell and a connecting piece connected coaxially; a tubular air outlet pipe is also arranged on one end of the cavity body close to the exhaust pipe; and the exhaust pipe is connected with the air outlet pipe and is connected to the L-shaped pipe through the air outlet pipe.
 5. The pipeline dredger according to claim 4, wherein a button for controlling the pressure release valve and an inflating mouth externally connected with an inflating device are arranged on the gun handle; an inflating opening communicated to the compressed air chamber is arranged in the connecting piece; the pressure release valve is communicated with the connecting pipe; and the inflating opening is communicated with the inflating mouth.
 6. The pipeline dredger according to claim 5, wherein a pressure gauge is also arranged on the gun handle; a three-way pipe is arranged in the middle of a first hose; a second hose is arranged between the three-way pipe and the pressure gauge; and the pressure gauge displays an intensity of pressure in the compressed air chamber and the chamber.
 7. The pipeline dredger according to claim 4, wherein an arc-shaped bulge is arranged at an opening of an end part of the air outlet pipe along a circumferential direction; the L-shaped pipe comprises a first air pipe and a second air pipe vertically connected; a spherical bayonet and a sealing knob sleeved on an outer ring of the spherical bayonet are arranged on an outer side of an end part of the first air pipe; a spherical chamber for inserting the arc-shaped bulge is arranged in the spherical bayonet; an internal diameter of the spherical chamber is equal to or less than a maximum external diameter of the arc-shaped bulge; a plurality of notches are arranged in the spherical bayonet along the circumferential direction of the opening; and the notches start from the opening and extend along a direction of the first air pipe.
 8. The pipeline dredger according to claim 4, wherein a safety plug and a safety plug hole penetrating through the connecting piece and communicated to the compressed air chamber are also disposed on the connecting piece; the safety plug is inserted into the safety plug hole; one end of the safety plug is sleeved with a safety spring; the safety spring generates an acting force facing the compressed air chamber to the safety plug; and the other end of the safety plug is sleeved with a plurality of safety washers and blocks the safety plug hole.
 9. The pipeline dredger according to claim 5, wherein a safety plug and a safety plug hole penetrating through the connecting piece and communicated to the compressed air chamber are also disposed on the connecting piece; the safety plug is inserted into the safety plug hole; one end of the safety plug is sleeved with a safety spring; the safety spring generates an acting force facing the compressed air chamber to the safety plug; and the other end of the safety plug is sleeved with a plurality of safety washers and blocks the safety plug hole.
 10. The pipeline dredger according to claim 6, wherein a safety plug and a safety plug hole penetrating through the connecting piece and communicated to the compressed air chamber are also disposed on the connecting piece; the safety plug is inserted into the safety plug hole; one end of the safety plug is sleeved with a safety spring; the safety spring generates an acting force facing the compressed air chamber to the safety plug; and the other end of the safety plug is sleeved with a plurality of safety washers and blocks the safety plug hole.
 11. The pipeline dredger according to claim 7, wherein a safety plug and a safety plug hole penetrating through the connecting piece and communicated to the compressed air chamber are also disposed on the connecting piece; the safety plug is inserted into the safety plug hole; one end of the safety plug is sleeved with a safety spring; the safety spring generates an acting force facing the compressed air chamber to the safety plug; and the other end of the safety plug is sleeved with a plurality of safety washers and blocks the safety plug hole.
 12. The pipeline dredger according to claim 1, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 13. The pipeline dredger according to claim 2, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 14. The pipeline dredger according to claim 3, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 15. The pipeline dredger according to claim 4, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 16. The pipeline dredger according to claim 5, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 17. The pipeline dredger according to claim 6, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 18. The pipeline dredger according to claim 7, wherein the sealing apparatus further comprises a pressurization airbag connected with the air-filled bag; the pressurization airbag inflates the air-filled bag; and the air-filled bag is made of elastic deformable material.
 19. The pipeline dredger according to claim 12, wherein an air delivery pipe is arranged between the air-filled bag and the pressurization airbag; a deflation valve is arranged on the air delivery pipe; an air inlet hole for a unidirectional air intake is formed in the pressurization airbag; and the deflation valve can be pressed to discharge inflated air in the air-filled bag. 